Who is BTS, and why did the K-pop band win a Billboard Music Award?

Move over PSY – Korean boy band BTS just became the first K-pop group to win a Billboard Music Award
Thanks to their huge fan base – both in South Korea and overseas – BTS took home the Top Social Artist award at the Billboard Music Awards yesterday in Las Vegas.
“Still cannot believe that we are standing here,” said BTS member Kim Nam-joon, better known as Rap Monster , when accepting the award on stage. The group also thanked fans for their support.
The group took to social media to celebrate in a group selfie.
— 방탄소년단 (@BTS_twt) 2017년 5월 22일
Previous Top Social Artist award winners and nominees include Justin Bieber, Selena Gomez, Taylor Swift and Ariana Grande.
The seven-member boy group made their debut in 2013. Their second full album titled Wings launched to number 26 on the US Billboard 200 as the highest chart ranking for a K-pop album ever.
BTS won Artist of the Year at last year’s Mnet Asian Music Awards which took place in Hong Kong. Their concerts last week at Hong Kong’s AsiaWorld-Expo were completely sold out.